Today, due to the tragic death of Amanda Asay, I learned the English term, "tree well", which is (quote from wikipedia):
A tree well, also known as a spruce trap, is the space around a tree under its branches that does not get the same amount of snow as the surrounding open space. This creates a void or area of loose snow below the branches and around the trunk that is dangerous...
Since I've never in my life done anything close to skiing, snowboarding or snowmobiling, I googled what this term would be in Russian and came across the following phrases: "корневой колодец", "стволовой колодец", and "конус под елью".
None of them seems to be a convincingly common term, so the question is: What's the most common and widely accepted term for the phenomenon described in English as "tree well"?